#include<cstdio>
void xsprint(int x,int y,int num);
void xprint(int x,int y);
void xxprint(int x,int y,int num);
void zprint(int x,int y);
int a[501][501];
int m,n;
int flag;
int main()
{scanf("%d",&n);for(int i=0;i<n;i++){for(int j=0;j<n;j++)scanf("%d",&a[i][j]);}printf("%d",a[0][0]);zprint(0,0);
}
void xsprint(int x,int y)
{   if(x>=n&&y>=n)return;for(int i=1;;i++){if(y+i>=n||x-i<0){flag=i-1;zprint(x-flag,y+flag);return ;}elseprintf(" %d",a[x-i][y+i]);}}
void xprint(int x,int y)
{if(x+1>=n&&y+1>=n)return;else if(x+1>=n){printf(" %d",a[x][y+1]);xsprint(x,y+1);return;}else{printf(" %d",a[x+1][y]);xsprint(x+1,y);}
}
void xxprint(int x,int y)
{  	if(x>=n&&y>=n)return;for(int i=1;;i++){if(x+i>=n||y-i<0){flag=i-1;xprint(x+flag,y-flag);return;}elseprintf(" %d",a[x+i][y-i]);}}
void zprint(int x,int y)
{if(y+1>=n&&x+1>=n)return;else if(y+1>=n){printf(" %d",a[x+1][y]);xxprint(x+1,y);}else{printf(" %d",a[x][y+1]);xxprint(x,y+1);}
}